[unreadable] Positron emission tomography (PET) plays a pivotal role in clinical evaluation of cancer using 18F Fluorodeoxyglucose (FDG) as a glucose analog. Small animal PET imaging fulfills a vital need to measure and visualize regional metabolism and other physiological functions in the study of cancer biology using rodent models. This Shared Instrumentation Grant seeks to fund the acquisition of a high resolution, commercially available small animal PET scanner for enhancing currently funded research by NIH investigators. Specific research initiatives will focus on 1) the search for and use of new radiotracers, such as radio labeled reporter genes, receptor ligands, hypoxia imaging agents, and metabolic substrates, 2) optimization of diagnostic strategies by performing functional imaging of tumors, 3) determination of prognostic value of single or multiple PET studies with various radiotracers, and 4) optimization of PET for assessment of response to therapy (variables include agent, tumor type, treatment modality, and time after treatment). These related but diverse activities represent far too many types of investigations to be accomplished in properly controlled human studies conducted within constrained time periods This is why small animal PET imaging is becoming recognized as an absolutely essential tool for longitudinal assessment of tumor function. A measure of success of this proposal will be related to transforming the enormous potential of PET imaging into the routine diagnosis and care of cancer patients. [unreadable] [unreadable] A Model microPET R4 from Concorde Microsystems, Inc is requested which has an 8 cm axial field-of-view (FOV), 10 cm transverse FOV and sensitivity of 900 counts/sec/uCi The small animal PET instrument will be administratively integrated into the existing University of Iowa PET Imaging Center operation. Resources related to radiopharmaceutical production, instrument maintenance and service, data acquisition analysis, as well as training, will be shared with the research arm of the PET Imaging Center. Major users from the Departments of Radiology and Radiation Oncology are collaborating on projects. Additional new users from the university community will be identified through a competitive intramural pilot project format. [unreadable] [unreadable]